A bioeconomic model was built to assess the contribution of more selective trawl nets to the objectives of the European Multi-Annual Plan for demersal fisheries in the Western Mediterranean (WM MAP). The biological submodel was parameterized with age-structured population parameters for the five target stocks in the WM MAP (European hake, red mullet, deep-water rose shrimp, Nephrops and red shrimp) with a sixth stock combining the remaining commercial by catch and following a biomass dynamics model. The trawl fleet was composed of three fleet segments, according to Vessel Length class (VL1218, VL1824, VL2440), practicing two métiers: coastal mixed demersal fishery and deep-water crustacean fishery. The technological solutions analyzed are two simple technical modifications to the otter bottom trawl and based on i) using a panel of meshes turned 90° (T90) in the extension of the trawl net, and ii) inserting a selective grid built from 40 mm square mesh (SM40) netting into the extension of the trawl net. The Results show that, in terms of policy objectives, the reduction in the values of fishing mortality achieved with these selectivity modifications would be insufficient to reach the target fishing mortality at maximum sustainable yield (Fmsy) prescribed in the WM MAP by 2025. However, model results project a substantial recovery of hake and red mullet stock biomass. The recovery of these two important stocks would help improve the evolution of the economic indicators, resulting generally in higher income, profits and salaries in the short (2025) and mid term (2030).

建立了一个生物经济模型，以评估更具选择性的拖网对欧洲西地中海底栖渔业多年计划（WM MAP）目标的贡献。生物子模型使用 WM MAP 中五个目标种群（欧洲无须鳕、红鲻鱼、深水玫瑰虾、Nephrops 和红虾）的年龄结构种群参数进行参数化，第六个种群结合了剩余的商业捕捞和跟随生物质动力学模型。根据船舶长度等级（VL1218、VL1824、VL2440），拖网船队由三个船队组成，从事两个行业：沿海混合底层渔业和深水甲壳类渔业。所分析的技术解决方案是对水獭底拖网的两个简单技术修改，基于 i) 在拖网的延伸部分使用旋转 90° (T90) 的网格面板，以及 ii) 插入由 40 平方毫米构建的选择性网格网（SM40）网进入拖网的延伸部分。结果表明，就政策目标而言，通过这些选择性修改实现的捕捞死亡率值的降低不足以在 2025 年之前达到 WM MAP 中规定的最大可持续产量 (Fmsy) 的目标捕捞死亡率。然而，模型结果预测无须鳕和红鲻鱼种群生物量的大量恢复。这两个重要股票的复苏将有助于改善经济指标的演变，从而普遍提高收入，